A military chaplain ministers to military personnel and, in most cases, their families and civilians working for the military. In some cases they will also work with local civilians within a military area of operations.

Although the term chaplain originally had Christian roots,[1] it is generally used today in military organizations to describe all professionals specially trained to serve any spiritual need, regardless of religious affiliation. In addition to offering pastoral care to individuals, and supporting their religious rights and needs, military chaplains may also advise the executive on issues of religion, and ethics, morale and morals as affected by religion. They may also liaise with local religious leaders in an effort to understand the role of religion as a factor both in hostility and war and in reconciliation and peace.[2]

Military chaplains normally represent a religion or faith group but work with military personnel of all faiths and none. Some countries, like the Netherlands and Belgium,[3] also employ humanist chaplains who offer a non-religious approach to chaplain support.

In the United States, the term, nomination, is not generally applied to the process of becoming a military chaplain. Individuals volunteer, and if they are accepted, they are commissioned as military staff officers in the Chaplain Corps. Members of the clergy who meet the qualifications for service as an officer in the military are free to apply for service with any of the three United States Chaplain Corps: the Army, Navy, and Air Force each has a Chaplain Corps, with Navy chaplains also assigned to serve with Marine Corps units, Coast Guard units, and the Merchant Marine Academy. Some clergy, like rabbis, can apply without permission from any individual or organization within their faith group; others, in faith groups that have a hierarchy established to make decisions on the postings or positions of their members, must be granted permission from the appropriate official, such as the appropriate Bishop. As the application process proceeds, and the military determines whether the applicant will meet standards in areas such as health, physical fitness, age, education, citizenship, past criminal history, and suitability for service, which includes supporting the free exercise of religion for men and women of all faiths, an endorsement from an endorsing agency that is recognized by the Department of Defense, representing one or more faith groups in the United States, will be required, in part to ensure that the separation of church and state is honored. Neither the government as a whole nor the military in particular will be put into the position of determining whether an individual is a bona fide priest, minister, rabbi, imam, etc. (The requirement for such an endorsement has been in force since 1901, and today many of the various religious endorsing agencies work together under such non-governmental voluntary umbrella groups as the National Conference on Ministry to the Armed Forces.) Although ordination is usually required for chaplain service, some "equivalent" status is accepted for individuals from religious groups which do not have ordination, such as the Church of Christ. Additionally, in cases where an endorsing agency is not yet established for an individual's religion, it is possible for him or her to be endorsed by the endorsing agency of another group, a process which was followed for the first Muslim chaplains in the military. In any event, this endorsement is recognized as necessary, but not sufficient for acceptance as a chaplain: in other words, the military will not accept an individual for service as a chaplain, nor allow him or her to continue to serve, without such an endorsement remaining in force; however, the decision as to whether to accept that individual remains with the military service, and the individual can be rejected for a number of reasons, including the needs of the military, even with the endorsement of an endorsing agency.

The Geneva Conventions are silent on whether chaplains may bear arms. However, the Conventions do state (Protocol I, 8 June 1977, Art 43.2) that chaplains are non-combatants: they do not have the right to participate directly in hostilities.

It is generally assumed that during World War II, chaplains were unarmed. Crosby describes an incident where a US chaplain became a trained tank gunner and was removed from the military for this "entirely illegal, not to mention imprudent" action.[8] At least some British chaplains serving in the Far East, however, were armed: George MacDonald Fraser recalls[9] "the tall figure of the battalion chaplain, swinging along good style with his .38 on his hip" immediately behind the lead platoon during a battalion attack. Fraser asks, "if the padre shot [an enemy], what would the harvest be ... apart from three ringing cheers from the whole battalion?"[9]
The Reverend Leslie Hardman, the British Second Army's senior Jewish chaplain, who became well known for his work amongst the liberated prisoners after the capture of Bergen-Belsen concentration camp, was another who insisted on being armed while on active service.[10]

In recent years, both the UK and US have required chaplains, but not medical personnel, to be unarmed in combat, although the US does not prohibit chaplains from earning marksmanship awards or participating in marksmanship competitions. Other nations, notably Norway, Denmark and Sweden, and also Australia,[11] make it an issue of individual conscience. There are anecdotal accounts that even US and UK chaplains have at least occasionally unofficially borne weapons: Chaplain (then Captain) James D. Johnson, of the 9th Infantry Division, Mobile Riverine Force in Vietnam describes (Combat Chaplain: A Thirty-Year Vietnam Battle) carrying the M-16 rifle while embedded with a combat patrol. Since 1909 US chaplains on operations have been accompanied by an armed chaplain assistant.[12] However, perhaps on this occasion it was felt that an unarmed uniformed man would draw unwelcome attention.

Captured chaplains are not considered prisoners of war and must be returned to their home nation unless retained to minister to prisoners of war.[13]

In 2006, training materials obtained by US intelligence showed that insurgent snipers fighting in Iraq were urged to single out and attack engineers, medics, and chaplains on the theory that those casualties would demoralize entire enemy units.[14] Among the training materials, there included an insurgent sniper training manual that was posted on the Internet. Among its tips for shooting US troops, there read: "Killing doctors and chaplains is suggested as a means of psychological warfare."

Military chaplains are often supervised by a chaplain general or chief of chaplains, on the staff of the leader of the nation's military forces. In some countries, like Israel, Canada, and South Africa, one chief of chaplains/chaplain general serves in that position for all chaplains of all religions, in all branches of the military.[citation needed] In many other countries, such as France, there is a separate chaplain general/chief of chaplains for each faith group represented by chaplains.[citation needed] In other countries, like the United States, there is one chaplain general/chief of chaplains for each branch of the military. So, for example, in the United States, there is an Army, Navy, and Air Force chief of chaplains. They meet on as representatives to the Armed Forces Chaplains Board,[15] to discuss issues that cross service lines, but each reports as a staff officer of his or her service, to the Chief of Staff of the Army or Air Force, or the Chief of Naval Operations of the Navy. (In the United States, Navy chaplains serve Navy, Marine Corps and Coast Guard personnel. Navy chaplains also assigned to the Merchant Marine Academy, for Merchant Marine personnel.)

Besides the Military Rabbinate of Israel, today, military rabbis serve throughout several countries of the world, most notably in the US military forces, and various European armies.
Since the rise of the Christian religion in Europe and worldwide, as a matter of course Christians fought against Christians over and over again. During World War I, for the first time a substantial number of Jews served on all sides of the war, and so did military rabbis. As a result of 18th and 19th centuries` emancipation, military field rabbis served on all fronts and in all combating nations.

Badges and insignia vary widely across nations and services; though generally include some form of symbol specific to the individual chaplain's religion.

In addition to badges and insignias for individual chaplains, certain nations, including the United States, fly a Church or Worship Pennant during the time a chaplain leads a religious worship service, especially on ships at sea. On United States Navy ships it is the only pennant that flies above the United States flag.

Roman Catholic military chaplains served in the Argentine armed forces since the early nineteenth century, and wore officers´ uniforms and ranks.
However, the use of these was discontinued in the 1970s in the Army and the Air Force, and in the 2000s in the Navy, due to allegations of some chaplains supposedly abusing their military position and thus discouraging their subordinates to approach them when in need. Nevertheless, chaplains continue to wear combat uniform (but no rank insignia) when accompanying the troops in field operations or exercises, and are still considered as a part of the officers corps.
No specific provisions exist for the spiritual support to non-Catholics.

Chaplains in the Australian Defence Force (ADF) have almost the same status as chaplains in the British armed services. Chaplains in the Australian Army and Royal Australian Air Force (RAAF) are commissioned officers and wear the uniform of officers of their particular branch of the services as well as the rank to which they are qualified. Chaplains in the Australian Army and the Royal Australian Air Force begin their commission as a Captain (Army) or Flight Lieutenant (RAAF) respectively. There are five levels or "divisions" for the seniority of chaplains in the Australian Army and Air Force with each division corresponding to a worn rank. The highest "division" is Division 5 who are "principal chaplains," of which there are three per service representing the three major Christian denominations: Catholic, Anglican and Protestant. The principal chaplains of the Army wear the rank of brigadier and in the RAAF, air commodore. Australian Army chaplains, whatever their rank, are mostly referred to as "Padre" by officers and soldiers alike. The title is also widely used in the RAAF for their chaplains.

Like chaplains in the Australian Army and RAAF, Royal Australian Navy (RAN) chaplains are commissioned officers and wear the uniform of an RAN officer, but like chaplains in the British Royal Navy (RN) they do not wear a rank. Rather they wear the same cross and anchor emblem worn by RN chaplains on their shoulder rank slides and do not have gold braided rings or executive loops on their winter sleeve coat or summer shoulder boards. Like other chaplains in the ADF, Navy chaplains have five divisions of seniority. Whilst Australian Navy chaplains do not wear rank, they are accorded a certain rank for protocol and ceremonial occasions and for saluting purposes. Division 1, 2 and 3 Australian Navy chaplains are accorded the rank and status as Commander (Lieutenant Colonel equivalent in the Australian Army). Division 4 Australian Navy chaplains are accorded the rank and status of Captain (equiv. of Colonel). Division 5 Australian Navy chaplains are "principal chaplains," and these three chaplains, representing the three major Christian denominations: Catholic, Anglican and Protestant, are accorded the rank and status of commodore. The title "Padre" for chaplains is less common and not officially encouraged in the Royal Australian Navy, although it is known to be used by some sailors and Navy chaplains in preference to the more formal title of "chaplain" or form of address towards an officer such as "sir." Like British Royal Navy chaplains, Royal Australian Navy chaplains wear a slightly different peaked cap to other Navy officers which apparently was designed by Winston Churchill.[citation needed]

In the Australian Defence Force (ADF), the heads of military chaplaincy for those Christian denominations and of the Jewish faith that have an official association with the ADF, are also members of the ADF's "Religious Advisory Committee" (RAC). With respect to the Catholic and Anglican churches, their Bishops are members of RAC and they and the other members of RAC have the status of a two star General (US) or Major General (Australian Army), or Rear Admiral (RAN) or Air Vice-Marshal (RAAF).

The Anglican and Roman Catholic strands of Australian Defence Force Chaplaincy have websites that explain their church's mission within the Australian Defence Force.[19][20] While the Protestant strand does not have a website, one of their chaplains has a representative blog site.[21]

A cadre of Canadian service members, led by a chaplain, carry the transfer case

The Canadian Armed Forces Chaplaincy has approximately 192 Regular Force chaplains and 145 Reserve Force chaplains[25] representing the Protestant, Roman Catholic, Muslim and Jewish faiths. The mission of this Branch is to "support and enhance the effectiveness of the CF as a whole – its leadership, the individual men and women who serve and their families – through the provision of comprehensive religious and spiritual support, advice, and care."[26] The vision of the Chaplaincy is to "be an operationally relevant Chaplaincy that supports and cares for all CF personnel and their families, wherever they live and serve, empowering them spiritually and morally to meet the demands of military service."[26]

Their role is to:

Foster the religious, spiritual and moral well-being of members and their families

Offer a ministry of presence in a multitude of environments (at home and abroad)

Participate in the life of the worshipping community

Officiate at special functions

Advise the Commanding Officer regarding the spiritual and ethical well-being and morale of their unit

When offering prayers during parades and ceremonies, it is customary that the order to remove headdress be given to those on parade.[27] In November 2004, Court Martial Appeal Court of Canada ruled that this order was "not lawful"[28] since it unjustifiably required all attendees to show participation in a prayer that may not believe. Following this ruling, non-believers are now permitted to retain their headdress just like Jews and Sikhs do in accordance with their faith.[27]

There are 95 Church of Denmark military chaplains associated the Danish armed forces; serving all personnel regardless of their faith position.[29] The chaplains are outside the ranking system, and are therefore equal to all soldiers. They are allowed to wear uniforms and a sidearm for self-defense.[30]

During the Second World War or to Finland the Winter War, Continuation War, and Lapland War Finland was unique among German allied Axis powers in including Jewish soldiers in its military as well as having field chaplaincy services available for them.[31][32]

French military chaplains Jewish, Muslim and Catholic, Place de Strasbourg 2013

During the Middle Ages, the cloak of Saint Martin of Tours, (cappa Sancti Martini), one of the most sacred relics of the Frankish kings, would be carried everywhere the king went, even into battle, as a holy relic upon which oaths were sworn. The clergyman who served as custodian for the cloak in its reliquary was called a capellānus, and, by extension, all clergymen who officiated in reliquaries, sanctuaries, or chapels were eventually called cappellāni. This eventually gave chapelain in Old French and was borrowed into English.[33]

Saint Louis was the king who gave legal status to the military chaplains, since chaplains serving under their lord in the Crusades were the first to be militarized. In 1531, during the Battle of Kappel, the Swiss reformist Huldrych Zwingli became the very first Protestant military chaplain to be killed on the battlefield.

The modern French Aumônerie militaire (military chaplaincy) was created and instituted by a July 8, 1880 Act of Parliament, which sets forth how the chaplaincy functions with regard to the Catholic, Protestant, and Jewish faiths. The Secularism Act (1905), which establishes a strict separation of church and state in the French government, does not however apply to the military. The defense minister appoints three command-level military chaplains—one per faith—in charge of all chaplains. The chaplains, serving in the army, are assigned by one of these three military chaplains. The first Muslim chaplain-general, Abdelkader Arbi, was commissioned in 2006.[34]

French military chaplains wear a uniform since World War II, but have no rank or rank insignia. The modern military chaplaincy is rooted in that war, where military chaplains were incorporated in almost every Free French Forces fighting unit and made up of personnel from England, France, or any of its imperial domains. After the war, military chaplains were sent to occupation zones in Germany and Austria.

In the 1950s, military chaplains where sent in the French Union's territories, including Indochina and Algeria. In 1954, pastor Tissot was one of the last paratrooper volunteers to jump over the besieged Dien Bien Phu fortified camp in northern Vietnam. On May 7, he was made prisoner of the Viet Minh and sent to a re-education camp, deep in the jungle.

Since 1984, French military chaplains are involved in every military operation—including the Gulf War—from Rapid Reaction Force (Force d'Action Rapide) units to navy ships.

In France, the existence of military chaplains has come under debate because of the separation of Church and State; however, their position has been maintained as of 2004[update].[35]

Initially only Christian chaplains worked in German armies. Only after the French Revolution did Jews become citizens with equal rights in Germany for the first time. An integration of Jewish soldiers within the army gave the German Reich the opportunity to recognize the Jewish urge to fight for the German “Fatherland”. The times of common Christian suppression and supremachy status changed and more and more German Jews served in the liberal French Armies of the German territories under French influence, e.g. in the Bavarian army.

In Prussia, king Frederick the Great also showed religious tolerance, but in case of the Jews he exerted intolerance. The Jews were divided into six classes, and only the privileged first class had de facto equal rights as citizens. Very few Jewish soldiers in the Prussian army of the 18th century left historical traces, e.g. Konstantin Nathanel of Salomon, who was promoted to general in 1760. Although the Jewish presence in Germany is older than Christianity,[37] the first "field rabbinat" was introduced during World War I. The German Kaiserreich appointed c. 30 military rabbis. Field rabbi Dr. Leo Baeck wrote the “Israelite Field Prayer Book”.

German Christian Field Service for German Soldiers during WWII, the army chaplain gives segen to the German troops with "God with us" on their paddock,[38][39] 1941; 95% of all Germans being Christians[39]

Germany had a tradition of appointing Catholic and Evangelical military chaplains and Jewish military field rabbis. This was continued in the Army and Navy of the Wehrmacht, for the Roman Catholic and Protestant denominations only. A total of 95% of all Germans being Christian, German soldiers during Nazi times continued to belong to the churches and had the words "Gott mit uns" (God with us) on the belt buckles of every Army and Navy enlisted men and non-commissioned officers.[38][39] Despite this proportion of Christians, the totalitarian national socialistic government of the German Reich tried to weaken the authority and influence of the churches over their German adherents. Besides the international Jewish question, the international character of the Catholic church was another challenge. A few Catholics who devoutly resisted the Nazis, suffered imprisonment and hardship. The case was solved by the Reichskonkordat (1933) between the Holy See and Nazi Germany. The government of the German Reich early established an pastoral ministry for the German Army and the Reichskonkordat settled the appointment of an Army bishop. Therefore, the military chaplains could more freely operate out of the Catholic hierarchy. Franz Justus Rarkowski, S.M., became ordained the Catholic military Field Bishop (Feldbischof) of Nazi Germany in 1938 until 1945.

German military chaplains who served the Wehrmacht were part of the German mainstream and lent the Nazi war effort legitimacy. The Christian military chaplains served between strange poles. While the Nazi ideology was at its core pagan (the elite SS units never allowed chaplains), 95% of Germans were baptized Christians. German soldiers during the Nazi era continued to belong to the churches and had the words "Gott mit uns" (God with us) on their belt buckles. “Being a chaplain in the German army had always been a prestigious position and the Nazis wanted people who represented that old military tradition (..) and not sow discord or division. They wanted people who were not troublemakers.2[38] The German military chaplains mostly wanted to bring the word of the Christian God to men in the field and to deliver the sacraments, make their families proud and serve their country. “The motives of the chaplains were not unusual, (..) their noble, personal and professional motives turned them into a legitimating force in a war of annihilation.”[38] Military chaplains in Nazi Germany were rigorously screened. First, names were put on the desks of the local civilian bishops, and then the names had to be approved by the according ministry for church affairs. Eventually the names were cleared by the military’s chaplaincy office and the Gestapo ("Secret State Police").[38][40]

Throughout the Third Reich period, only the Army and Navy had military chaplains. When needed, other branches of the armed forces acquired chaplains from the Army or Navy or from nearby parish. In the Heer (Army), military chaplains were organized into Group 3b (Pastoral Group) of the General Army Office under the Army High Command. In mid 1935, four groups of military chaplains were introduced. In 1936, similar groups were introduced for the Kriegsmarine although the evolution over time was different. The groups are as follow.[41]

Oberpfarrer (Higher Priest)

Pfarrer (Priest)

Standortpfarrer im Hauptamt (Garrison Priest in Main Office)

Standortpfarrer im Nebenamt (Garrison Priest for Outside Appointment)

German military chaplains did not get into the ordinary military rank system, but received privileges like any other regular officers. Army chaplains had four different types of clothing:[42]

Feldbluse (Field Dress). Field dress was identical for enlisted men, non-commissioned officers, and officers, and was worn on the battlefield. For military chaplains, the field dress was worn with officer-quality collar patches and without shoulder boards. Long trousers with shoes or breeches with officer boots could be worn. Two-pronged officer's belt was used.

Dienstrock (Service Dress). Service dress was the typical dress for officers, with high quality materials and tailor made. For military chaplains, the field dress was worn with officer-quality collar patches and without shoulder boards. Service dress was normally used behind the lines although photographic evidences also show this kind of uniform was worn on the battlefield. Long trousers with shoes or breeches with officer boots could be worn. Two-pronged officer's belt was used, sometimes with cross strap.

Überrock (Frock Coat). Frock coat was used for formal occasions and when ordered, and worn over the service dress. The piping was violet.

Mantel (Overcoat). Overcoat worn by military chaplains was identical to those worn by officers. However, no shoulder boards were attached. This was worn over the field dress or service dress.

No weapon was permitted to be carried by chaplains, but one photographic evidence shows a chaplain with a pistol holster on his left waist.

Schirmmütze (Visor Cap). Officer-quality visor cap with violet as the branch color (Waffenfarbe) for military chaplains. Between the national eagle and cockade, there was a small Gothic cross, either made of metal or embroidered.

Feldmütze (Field Cap). Officer-quality field cap with silver pipings and violet soutache as the Waffenfarbe. Between the national eagle and cockade, there was a small Gothic cross, usually embroidered.

All the buttons, national eagles, cockades, Gothic crosses, and cap chinstraps were silver for military chaplains and gold for Field Bishops.
The collar patches had violet underlay and violet piping for Catholic chaplains, and field grey underlay and violet piping for Protestant (Evangelist) chaplains.

For the Kriegsmarine, the uniform was identical to naval jacket of regular officers, but without sleeve laces and with chaplain collar patches. The collar patches were different to those of the Army. Two-prong officer's belt or brocade belt could be worn.

Although the official regulation states that military chaplains had to wear golden pectoral cross, there were two standard-issue crosses that were worn:[41]

For Catholic chaplains, Corpus Christi was present on the cross. The cross itself was made either of metal or silver, with black wood insert. Long metal chains went through a loop at the top of the cross to be worn around the neck.

For Protestant (Evangelist) chaplains, the cross was plain and made of metal or silver. Long metal chains went through a loop at the top of the cross to be worn around the neck.

Photographic evidences show numerous variety of pectoral crosses worn by German military chaplains during World War II.

Oftentimes, German military chaplains were issued an armband with a red cross sign and violet stripe to show their neutrality on the battlefield. This was called Armbinde mit Neutralitätsabzeichen (Armband with Neutrality Sign).

Among other things, military chaplains also wore standard liturgical vestments such as chasuble, cope, and stole.

Catholic Archbishop Cardinal Bettinger visiting the German Western Front, 1916

German Kriegsmarine suitcase with altar dishes of a protestant military chaplain, 1940

Liberated foreign Protestant, Catholic and Jewish chaplains conduct funeral services for the reburial of 71 political prisoners, exhumed from a mass grave near Solingen, Germany, in front of the city hall, May 1945

Ecumenicism in line of succession: Dean Dr. Slaczka, Brig Gen Leidenberger, and Chaplain Weeke at a funeral service, ISAF, 2009

German religious constitutional law and its state-church law is involved in the democratic national identity of modern Germany, especially in various articles of the German Constitution. Initially, a "military-chaplaincy" contract was only signed between the state and the Protestant Church, but was extended to all other religious communities for reasons of parity.[43] Furthermore, the 1930s Reichskonkordat between the Holy See and Germany is still in force. In Germany, military chaplains of the Bundeswehr have no rank but have a special civilian status as part of the armed forces.

The Military Rabbinate is a unit in the Israel Defense Forces that provides religious services for military personnel, Jewish and non-Jewish, and makes decisions on issues of religion and military affairs. The Military Rabbinate is headed by the Chief Military Rabbi, who carries the rank of a Brigadier General.

The Military Rabbinate constitutes the body responsible for religious institutions in the military. In every unit or military base there are Military Rabbinate military personnel assigned responsibility for conducting or coordinating religious services, overseeing the kosher operation of the kitchen, and the maintenance of the synagogue and religious supplies. Actively serving military personnel can request Military Rabbinate representatives to perform marriage ceremonies and brit mila, circumcision ceremonies, for babies. The unit also oversees the legal and religious certification of marriages and divorces of individuals during their military service.

The Military Rabbinate is responsible for treating the bodies of soldiers in accordance with religious law, including the identifications and post-mortem treatment of bodies, and conducting military funerals. The Military Rabbinate also coordinates the burial of enemy soldiers and the exhuming of bodies in conjunction with prisoner exchanges.

The Military Rabbinate was founded in 1948 by Rabbi Shlomo Goren, who headed it until 1968.

The Netherlands has chaplains of Protestant, Catholic, Jewish, Muslim, Hindu, and humanist faiths, provided by the De Diensten Geestelijke Verzorging (DGV) or the Spiritual Care Services. Chaplains are trained in Vormingscentrum Landgoed Beukbergen.[44]

Since 1968, however, all chaplains have been senior officers and accorded the protocol status of colonel / captain (navy). They carry the military rank of chaplain and the rank insignia, which is unique to the Chaplains Service, comprises a Chi Rho monogramme[47] surrounded by a triangle. The monogramme represents the first two letters of Christ in Greek. It originates from the days of Constantine, the first Emperor of Rome to grant religious freedom to Christians. His own conversion to the Christian faith was initiated by a dream in which the Chi-Rho monogramme appeared to him. The triangle surrounding the monogramme is the symbolic representation of the Holy Trinity.

In the SANDF Chaplain Service, the Hindu faith is represented by a Regular Force chaplain. The rank is Cpln (Vipra) and the mode of address Vipra. The rank insignia is a deepa (lamp) with flame. This is the symbolic representation of enlightenment, the life objective of all Hindus.

The Muslims do not have Regular Force chaplains in the SANDF because they are small in number. They are however served by part-time workers through the Chaplains Service of the SANDF and are addressed according to their religious customs as imams.

Christian chaplains are generally referred to and addressed as Padre. They may however, be addressed according to the practice of their religious bodies e.g., Father, Pastor, Umfundisi (Zulu and Xhosa), Moruti (Sotho), Dominee (Afrikaans) etc. The official written form of address is Cpln (for chaplain) followed by the appropriate ecclesiastical title of the respective chaplain e.g., Cpln (Rev), Cpln (Fr), Cpln (Pastor), Cpln, etc.[48]

Along with chaplains from many other nations in the southern region of the continent of Africa, South African chaplains participate in SARMCA, the South Africa Regional Military Chaplains Association, which is a component organization of SADC, the Southern African Development Community.

Father C. V. Murphy carries out Mass in a Dutch field in the front line, 6 October 1944.

The first English military-oriented chaplains were priests on board proto-naval vessels during the eighth century AD. Land based chaplains appeared during the reign of King Edward I, although their duties included jobs that today would come under the jurisdiction of military engineers and medicalofficers. A priest attached to a feudal noble household would follow his liege lord into battle. In 1796 the Parliament of Great Britain passed a Royal Warrant that established the Army Chaplains' Department in the British Army. The Department was awarded its "Royal" prefix in 1919 in recognition of their chaplains' service during World War I.

The current form of military chaplain dates from the era of the First World War. A chaplain provides spiritual and pastoral support for service personnel, including the conduct of religious services at sea or in the field. In the Royal Navy chaplains are traditionally addressed by their Christian name, or with one of many nicknames (Bish; Sin-Bosun; Devil Dodger; Sky-Pilot etc.). In the British Army and Royal Air Force, chaplains are traditionally referred to (and addressed) as padre or as Sir/Ma'am (although not the latter in the RAF).

In the Royal Navy chaplains have no rank other than "chaplain" while in the British Army they hold commissioned relative rank but are universally referred to as Padre. On the foundation of the Royal Air Force Chaplains' Branch an attempt was made to amalgamate these differing systems creating "Relative Rank", where rank is worn but without executive authority. In practice chaplains of all three services work in similar ways using what influence and authority they have on behalf of those who consult them or seek their advice.

Monument to Catholic Father Francis P. Duffy in Times Square in front of a Celtic cross. He typically was involved in combat and became the most highly decorated cleric in the history of the US Army

In the United States, military chaplains have an officer's rank based on their years of service and promotion selection from among their peers. Chaplains serving in the US Armed Forces wear the uniform of their respective branch of service, and normally wear clerical attire only during the performance of a religious service. The position of rank and chaplain faith group insignia varies in each military department and may vary significantly from one type of uniform to another within a military department. The US Army, Air Force, and Navy (as a component of the Department of the Navy the Marine Corps is supplied by USN chaplains) require an 'ecclesiastical endorsement' from the candidate's faith group (which in the case of the Navy must be one registered with the DoD).[54][55][56]

The Civil Air Patrol, the volunteer Auxiliary of the USAF, also has chaplains, who must meet the same standards for appointment as active-duty Air Force, Air Force Reserve and Air National Guard chaplains. They wear the same insignia as USAF chaplains and can be called upon to assist Air Force chaplains.[57]

US military chaplains, both individuals and in groups, have been involved in a number of controversies. Complaints have been made against chaplains for mandatory prayers, coercion, and using government money to promote Evangelical Christianity.[58] Groups representing atheists have pushed for the appointment of someone representing their viewpoint to the chaplaincy.[59] Individual cases include that of Air Force Lt. Col. Garland Robertson, discharged in 1993 after expressing political opinions in a letter to the Abilene Reporter-News[60] and Navy Chaplain Lt. Gordon Klingenschmitt who, against direct orders to him personally, as well as military law and tradition, protested openly and publicly while in uniform against military policies which he believed restricted the free exercise of his religion.[61]

The constitutionality of the US chaplaincy has been the subject of legal challenges and scholarly dispute. One appellate case, Katcoff v. Marsh (1985) upheld the system as a permissible attempt to support service members in the "free exercise" of their religious beliefs, though others have described the details of the chaplaincy system as violations of the legal principles that the federal government maintain neutrality and avoid becoming entangled in religious affairs.